18 research outputs found
Pratiques agricoles et perceptions paysannes des impacts environnementaux de la cotonculture dans la province de la KOMPIENGA (Burkina Faso)
La dĂ©gradation des Ă©cosystĂšmes et dâune maniĂšre gĂ©nĂ©rale de lâenvironnement au Burkina Faso est liĂ©e aux facteurs anthropiques, notamment les activitĂ©s agricoles. Lâobjectif de cette Ă©tude est de mettre en exergue les pratiques agricoles, les perceptions paysannes des impacts environnementaux et les risques de dĂ©gradation des ressources naturelles dans la zone cotonniĂšre de lâEst (Province de la Kompienga). Par le biais (i) dâune enquĂȘte auprĂšs dâun Ă©chantillon de 60 UnitĂ©s de Production CotonniĂšre (UPC), (ii) des interviews semi structurĂ©es avec des maraĂźchers (12), des apiculteurs (15), des pĂȘcheurs (29), des Ă©leveurs (54) et des membres de comitĂ©s villageois de gestion des forĂȘts (23), (iii) et des investigations sur les pratiques agricoles, lâĂ©tude a Ă©tĂ© conduite. Les rĂ©sultats ont rĂ©vĂ©lĂ© une pression fonciĂšre dans la zone avec pour corollaire un abandon des techniques de conservation et de restauration des sols. Lâusage des fertilisants organiques est peu rĂ©pandu. LâĂ©tude a rĂ©vĂ©lĂ© que 8 types de rotations culturales sont pratiquĂ©es dans la zone. Le type de rotation culturale coton-cĂ©rĂ©ales-coton est pratiquĂ© par 63% des cotonculteurs. Les perceptions paysannes sur la dĂ©gradation des ressources vĂ©gĂ©tales, les risques encourus par lâĂ©cologie apicole ainsi que des effets nĂ©gatifs des fertilisants chimiques sur lâeau et les sols sont diversement apprĂ©ciĂ©s. Face Ă cette situation, il est urgent pour les producteurs de coton dâutiliser les engrais organiques et dâadopter des techniques de conservation et de restauration des sols pour prĂ©server lâexploitation durable des ressources naturelles de la zone.Mots-clĂ©s : Culture de coton; Pratiques agricoles; Pression fonciĂšre; Risque de dĂ©gradation de lâenvironnement; Burkina Faso
Biogas production using water hyacinths to meet collective energy needs in a sahelian country
This paper presents a pilot project that investigates the possibility of producing biogas from a mixture of water hyacinth and fresh rumen residue â replacing ïŹrewood as a source of fuel â to meet the energy needs of a maternity facility in Niamey (Niger). The discontinuous-type installation (batch reactors) is made up of six digesters measuring 5 m3 each. The output during hot and cool seasons, 0.52 m3 and 0.29 m3 respectively of biogas per m3 of digester per day, has met the energy needs of the maternity facility, estimated at 8 m3 of biogas per day. The study revealed strong seasonal variations: output during the hot season is approximatively 1.8 times greater than it is during the cool season. Large quantities of water hyacinth, an invasive plant present in Niger since 1986, are manually harvested in aquatic environments. The project is run by a local NGO, the Groupe dâInitiative pour les Energies Renouvelables (GIER), and supported by UNICEF and the Niger Basin Authority. The duration of the project is 8 months.Ce papier prĂ©sente un projet pilote vĂ©rifiant la possibilitĂ© de produire du biogaz Ă partir dâun mĂ©lange de jacinthe dâeau et de rĂ©sidu frais de rumen, en substitution au bois de chauffe pour satisfaire aux besoins en Ă©nergie dâune maternitĂ© de Niamey (Niger). Lâinstallation de type discontinu (rĂ©acteurs batch) est composĂ©e de six digesteurs de 5 m3. Les rendements en saison chaude et en saison fraĂźche, respectivement 0,52 et de 0,29 m3 de biogaz par m3 de digesteur par jour et ont permis de couvrir les besoins de la maternitĂ© Ă©valuĂ©s Ă 8 m3 de biogaz par jour. LâĂ©tude rĂ©vĂšle une forte variation saisonniĂšre : le rendement en saison chaude est dâenviron 1,8 fois supĂ©rieur Ă celle de la saison fraĂźche. La jacinthe dâeau est une plante envahissante prĂ©sente au Niger depuis 1986, dont des quantitĂ©s importantes sont rĂ©coltĂ©es en  milieux aquatiques. Le projet est portĂ© par une ONG locale, le Groupe dâInitiative pour les Energies Renouvelables (GIER) et est supportĂ© par lâUNICEF et lâAutoritĂ© du Bassin du Niger. La durĂ©e du projet est fixĂ©e Ă huit mois.Presenta un proyecto piloto que investiga la posibilidad de producir biogĂĄs a partir de jacintos de agua y residuos ruminales frescos, que sustituyen a la madera como fuente de combustible, para cubrir las necesidades energĂ©ticas del hospital de maternidad de Niamey (NĂger). La instalaciĂłn activada en discontinuo (reactores secuenciales) estĂĄ formada por seis digestores de 5 m3 cada uno. La producciĂłn durante las estaciones de calor y frĂo, 0,52 m3 y 0,29 m3 de biogĂĄs respectivamente por m3 de digestor al dĂa, ha cubierto las necesidades energĂ©ticas del hospital de maternidad, que se calcula en 8 m3 de biogĂĄs al dĂa. El estudio ha revelado importantes variaciones segĂșn la estaciĂłn: la producciĂłn durante la estaciĂłn de calor es aproximadamente 1,8 veces mayor que la cantidad producida durante la temporada de frĂo. En el medio acuĂĄtico se cosechan manualmente grandes cantidades de jacinto, una planta invasiva presente en NĂger desde 1986. El proyecto estĂĄ dirigido por una ONG local, GIER, y apoyado por UNICEF y la Autoridad de Cuencas de NĂger. El proyecto tiene una duraciĂłn de 8 meses
Teneurs en coumarines de 15 ligneux fourragers du Burkina Faso
Les antinutritionnels ont Ă©tĂ© le plus souvent ignorĂ©s dans lâĂ©valuation de la qualitĂ© des fourrages ligneux dont la part augmente continuellement dans le bol alimentaire des ruminants au Burkina Faso. Lâobjectif de lâĂ©tude a Ă©tĂ© de caractĂ©riser et de quantifier les coumarines dans les feuilles et/ou les fruits de 15 ligneux fourragers couramment appĂ©tĂ©s par les ruminants Ă Diarabakoko et Dionona. Des tests de caractĂ©risation en tubes ont Ă©tĂ© rĂ©alisĂ©s sur les Ă©chantillons frais collectĂ©s pour dĂ©tecter la prĂ©sence des coumarines. Des dosages spectrophotomĂ©triques des coumarines ont Ă©tĂ© Ă©galement rĂ©alisĂ©s Ă partir des extraits frais des Ă©chantillons. LâĂ©tude a rĂ©vĂ©lĂ© la prĂ©sence des coumarines chez toutes les espĂšces Ă des teneurs oscillant respectivement entre 10,590 ±0,354 et 31,174±0,477 ÎŒg EC/g dâextraits frais des feuilles et entre 1,250 ±0,014 et 22,899±0,561 ÎŒg EC/g dâextraits frais des fruits (PË0,05). Lâanalyse des variances a permis de distinguer 2 classes de teneurs en coumarines des feuilles dont la premiĂšre a les plus faibles valeurs. Nos rĂ©sultats constituent des critĂšres supplĂ©mentaires pour le choix des ligneux fourragers en amĂ©nagement pastoral et en agroforesterie. Ils montrent aussi que le fourrage (feuilles et fruits) des espĂšces Ă©tudiĂ©es peut contribuer sans danger Ă la supplĂ©mentation des ruminants. Mots clĂ©s : Alimentation, antinutritionnels, fourrage, amĂ©nagement pastoral, ruminant
Polyphenolic composition of Lantana camara and Lippia chevalieri, and their Antioxidant and Antimicrobial Activities
In the present study, the antioxidant and antibacterial activities of methanolic extracts of two Verbenaceae (Lantana camara L. and Lippia chevalieri Moldenke: aerial part) were investigated. Their polyphenolic composition in the ethyl acetate and aqueous fractions were characterized by HPLC-DAD. The antioxidant capability of the methanolic extracts was assessed by the Ferric Reducing Antioxidant Power (FRAP) and the scavenging activity of the free radical 2,2-diphenyl-1-picrylhydrazyl (DPPH). The Minimum Inhibitory Concentrations (MIC) of the methanolic extracts (25 ”g mL-1), and the minimum bactericidal concentrations (MBC) (12.5 ”g mL-1) against 13 pathogenic bacteria and four serotyped bacteria from the American Type Culture Collection (ATCC) were also determined by the agar-well diffusion method. The results indicated that the L. chevalieri extracts are rich in phenolic compounds (among the 27 polyphenolic compounds detected, 20 belong to L. chevalieri) and showed the highest antioxidant activities, simultaneously on iron (III) to iron (II)-reducing activity and the radical scavenging activity. However, L. camara displayed the best and the broadest antimicrobial spectrum, especially on Shigella flexneri and Pantoea sp. (two Gram-negative strains of bacteria). The nature of polyphenolics compounds detected (phenol acid and flavone) in the L. camara can justify this activity.Key words: Verbenaceae, HPLC-DAD, antioxidant activity, antimicrobial activity, polyphenolic compound
Phytochemical composition, Antioxidant and Anti-inflammatory potential of bioactive fractions from extracts of three medicinal plants traditionally used to treat liver diseases in Burkina Faso
Our aim in this study concerning the ethyl acetate and dichloromethane fractions was to provide a scientific basis for the treatment of hepatitis B in Burkina Faso of these three ethnomedicinal plants. As a result, we evaluated polyphenol content, antioxidant and anti-inflammatory evaluated by lipoxygenase (LOX) inhibitory and Xanthine Oxidase (XO) activities of aqueous acetone bioactive fractions from three species of Malvaceae (Sida cordifolia, Sida rhombifolia, S. urens). Folin-ciocalteu; AlCl3 methods and tannic acid respectively were used for polyphenol content research. The antioxidant activity of the samples was evaluate using three separate methods, inhibition of free radical 2,2-diphenyl-1-picrylhydramzyl (DPPH), ABTS radical cation decolorization assay, Iron (III) to iron (II) reduction activity (FRAP). For anti-inflammatoty activity, lypoxygenase and xanthine oxidase inhibitory activities were used. Finally, in this study, the ethyl acetate fraction has shown the best results comparatively to the dichloromethane fraction. Keywords: Polyphenol, Antioxidant, anti-inflammatory, Medicinal plants, hepatitis B
Phytochemical composition, Antioxidant and Anti-inflammatory potential of bioactive fractions from extracts of three medicinal plants traditionally used to treat liver diseases in Burkina Faso
Our aim in this study concerning the ethyl acetate and dichloromethane fractions was to provide a scientific basis for the treatment of hepatitis B in Burkina Faso of these three ethnomedicinal plants. As a result, we evaluated polyphenol content, antioxidant and anti-inflammatory evaluated by lipoxygenase (LOX) inhibitory and Xanthine Oxidase (XO) activities of aqueous acetone bioactive fractions from three species of Malvaceae (Sida cordifolia, Sida rhombifolia, S. urens). Folin-ciocalteu; AlCl3 methods and tannic acid respectively were used for polyphenol content research. The antioxidant activity of the samples was evaluate using three separate methods, inhibition of free radical 2,2-diphenyl-1-picrylhydramzyl (DPPH), ABTS radical cation decolorization assay, Iron (III) to iron (II) reduction activity (FRAP). For anti-inflammatoty activity, lypoxygenase and xanthine oxidase inhibitory activities were used. Finally, in this study, the ethyl acetate fraction has shown the best results comparatively to the dichloromethane fraction. Keywords: Polyphenol, Antioxidant, anti-inflammatory, Medicinal plants, hepatitis B
Biogas production using water hyacinths to meet collective energy needs in a sahelian country
This paper presents a pilot project that investigates the possibility of producing biogas from a mixture of water hyacinth and fresh rumen residue â replacing ïŹrewood as a source of fuel â to meet the energy needs of a maternity facility in Niamey (Niger). The discontinuous-type installation (batch reactors) is made up of six digesters measuring 5 m3 each. The output during hot and cool seasons, 0.52 m3 and 0.29 m3 respectively of biogas per m3 of digester per day, has met the energy needs of the maternity facility, estimated at 8 m3 of biogas per day. The study revealed strong seasonal variations: output during the hot season is approximatively 1.8 times greater than it is during the cool season. Large quantities of water hyacinth, an invasive plant present in Niger since 1986, are manually harvested in aquatic environments. The project is run by a local NGO, the Groupe dâInitiative pour les Energies Renouvelables (GIER), and supported by UNICEF and the Niger Basin Authority. The duration of the project is 8 months
Plantes utilisĂ©es pour attirer les essaims de lâabeille domestique (Apis mellifera adansonii Latreille) au Burkina Faso
Les pratiques apicoles modernes utilisĂ©es pour attirer les essaims de lâabeille domestique dans les ruches engendrent des coĂ»ts Ă©levĂ©s Ă cause du matĂ©riel qui est souvent importĂ©. Or au niveau des pratiques traditionnelles, il existe un ensemble de plantes qui sont utilisĂ©es depuis des temps lointains pour attirer les essaims dâabeilles dans les ruches traditionnelles. Une enquĂȘte "ethnoapicole" menĂ©e dans deux zones phytogĂ©ographiques du Burkina Faso a permis de recenser treize espĂšces vĂ©gĂ©tales reparties en douze genres et huit familles botaniques qui sont utilisĂ©es par les apiculteurs traditionnels pour attirer les essaims dâApis mellifera adansonii Latreille. Un meilleur conditionnement de ces plantes permettrait de les utiliser avec les ruches modernes pour leur colonisation, constituant ainsi une alternative Ă lâimportation du matĂ©riel de capture et/ou dâattraction des essaims, une rĂ©duction des frais dâinstallation des ruchers pour un dĂ©veloppement et une extension de lâapiculture moderne dans les zones rurales des pays africains.Mots clĂ©s : plante, "ethnoapicole", apiculture, essaim, Burkina Faso
DE LA LOGIQUE D'OCCUPATION SPATIALE A L'EMERGENCE DES RISQUES ENVIRONNEMENTAUX DANS LA ZONE SUD-SOUDANIENNE DU BURKINA FASO: CAS DE L'INTERACTION ENTRE LA CULTURE DE COTON ET L'ELEVAGE
N° ISBN - 978-2-7380-1284-5International audienceThe province of Kompienga has favorable agro-climatic characteristics for agricultural and livestock activities development. Besides these advantages, there is the fact that this region has a low density (10.8 habitants per km2) compared to the national average (51.8 habitants per km2) which offers land for cultivation. However, nowadays the combined effects of migration and adoption of technological packages in intensifying the cultivation of cotton, this situation is out of date and from that time the area is facing competition for the occupation of natural resources. This study establishes an environmental diagnosis of two activities (livestock and cotton farm) for the purpose of laying bare their interaction through surveys and observations on agricultural practices. The investigations reveal that the contribution of animals (plowing, weeding, fertilizer and animal traction) for increasing crop yields is very well received by producers. The income from cotton sales contribute to the establishment of agro-pastoral people. The main sources of conflict are identified damage caused by animals on crops, lack of access to pastoral resources (pasture, water) in animals and health hazards with the spreading of pesticides on field borders. This study shows that livestock and cotton farm maintain a strong but fragile relationship dynamics in this region. This dynamic can be enhanced by the emergence of a policy of integrated management of natural resources taking the negative environmental externalities highlighted